Global Machine Vision Market Embraces Industry Standards

Unless you are an expert engineer that lives and breathes the stuff, it can be difficult to get excited about technical standards. But like so many things in life, it’s often the hardest job, the longest slog, done by the few that drastically changes the lives of many for the better.

“Standards are a double-edged sword,” says Dr. Rex Lee, president of Pyramid Imaging (Tampa, Florida) and AIA board member. “Every manufacturer wishes their proprietary technology was used worldwide, but standards allow end users to be able to pick and play whatever component is best suited for their system. Ultimately that creates more demand for machine vision. The AIA standards committees have been doing a great job moving machine vision standards forward.”

This year is a great example of how standards help to grow machine vision markets. Two of the biggest technical standard developments relate to AIA’s Camera Link machine vision standard.

The headline announcement is likely that Camera Link will see a 3.0. First, a little background: The Camera Link standard has always called for the use of National Semiconductor’s chipset. It worked, was cost-effective, and was readily available. But as camera manufacturers utilize every square millimeter of board space to enable ever-smaller products, many of them developed their own Camera Link implementation using field programmable gate arrays (FPGAs).

“In some cases, the FPGA implementation was even more robust than the chipset, but not in every case,” says Steve Kinney, chairman of the Camera Link technical committee and general manager of business development at LED light manufacturer CCS America (Burlington, Massachusetts).

Since there wasn’t a standard FPGA reference implementation, the variation in performance contributed to concerns about Camera Link cable performance and testing, and inhibited Camera Link PlugFests ¬— gatherings that allow the makers of USB3 Vision and GigE Vision products to independently certify their products to a universal standard.

The other major change — the inclusion of GenICam, including GenCP and Gen TL layers — will make Camera Link products self-discoverable and self-configurable, eliminating the need for frame-grabber configuration files. Camera Link will move into the plug-and-play generation enjoyed by the other newer standards.

The inclusion of the GenICam layer also will help enable the creation of a software validation frameworkframework. This plus a standardized LFSR test pattern will enable PlugFest-style qualification of cameras, frame grabbers, FPGA cores, and cables. This ensures a higher level of qualification and verified interoperability than previously possible, giving users confidence in the performance and compatibility of various manufacturers’ Camera Link products.

“These changes don’t fundamentally change the Camera Link standard. Rather, they are aimed at enhancing operability to guarantee the best user experience,” Kinney says. “Some folks may be surprised that we’re going to develop a 3.0 standard because they think the Camera Link user base is shrinking, but that is just not true. While Camera Link market share has shrunk from its peak as the primary digital interface standard for industrial cameras and frame grabbers, the overall market today is so much larger that the total volume of Camera Link products sold is stable or actually increasing for some manufacturers. Camera Link remains a viable and important interface for a performance-based segment of the machine vision market and the manufacturers catering to them.”

Usability Just One of CLHS Improvements
Unlike the Camera Link standard, Camera Link HS (CLHS) has long used FPGAs as protocol chipsets and offers IP cores through the AIA. CLHS also leverages copper and fiber-optic cabling developed for the telecommunications market to ensure reliable, risk-free data transfer.

“The IP cores embed the Camera Link HS protocol, providing a simple and consistent parallel interface to the user’s FPGA,” explains Michael Miethig, R&D camera development manager for Teledyne DALSA (Waterloo, Ontario, Canada) and chairman of the CLHS standards committee. “These cores have proven effective in quick system bring-up and interoperability of cameras and frame grabbers from multiple vendors and end customers.”

Improvements planned for the CLHS standard include adding a multilane 10 Gbps connector, increasing M protocol speed from a base of 3.125 up to 5 and 6.25 Gbps, and extending cable-length measurement for fiber cables longer than 300 meters to avoid command resends. CLHS v2 also will support 3D data transfers; multiple ROIs, each with its own pixel type; simplified bootstrap registers; and enhanced video packet structures.

AIA’s GigE Vision committee is finalizing the content of 3D data support which is now ready for integration into the text of the standard, including the necessary changes to the GenICam Pixel Format Naming Convention. The committee has also formed two official sub-committees: Mechanical headed by Marcel Naggatz from Baumer and Validation Framework headed by James Falconer from Pleora. Finally, the committee has developed at a GigE Vision accessory program titled, “Certified to Use in GigE Vision Systems,” to allow the registration of products that have been designed to supplement GigE Vision products, but are not implementing the full GigE Vision standard. For instance, this could be a Power-over-Ethernet switch that offers locking connectors compatible with GigE Vision cameras.

As for those standards committees doing the longest slog? “It turns out that it is really a collegial group of experts who have quite a good time doing that hard work,” says Bob McCurrach, AIA’s director of standards development. “They meet face to face twice a year all over the globe, have developed friendships with people from vastly different cultures, and have benefited their companies along the way. Not a bad deal.”

The next face-to-face meeting of the Camera Link committees, as well as AIA’s GigE Vision and USB3 Vision standards committees, will take place at the Euresys offices in Liege, Belgium, during the week of October 10, 2017. Any AIA, CMVU, EMVA, JIIA, or VDMA members with interest in or input to the proposed Camera Link standard changes discussed above, or any other AIA technical standard, should contact McCurrach at  (734) 994-6088.